This invention relates to a setting of metallic parts for setting a facet cut precious stone to jewelry such as a pendant, a ring, a pierced earring, an earring, and further relates to a method of setting a facet cut precious stone by setting metallic parts to jewelry.
In a conventional method of setting a facet cut precious stone to jewelry by using setting metallic parts, more than one prong was necessary to press the crown of the facet cut precious stone from above.
Also, the girdle of the facet cut precious stone was held by a ring-shape sheet from below.
On the other hand, as shown in FIGS. 1 and 2, a setting of metallic parts for setting a facet cut precious stone may comprise one prong portion for pressing the crown of the facet cut precious stone or the crown and the table of the facet cut precious stone, and one concave-shaped inserting portion for holding the culet in the vicinity of the facet cut precious stone.
Compared to the conventional setting method, the latter setting method has an advantage that much more light enters the facet cut precious stone since the upper facets of the facet cut precious stone are not being covered by many prongs, and the precious stone can maintain its brightness and beauty after the setting.
However, the latter setting of metallic parts has a disadvantage in the respect of it's strength. Since the facet cut precious stone is held by only one prong portion and one inserting portion from one side of the stone, when some accident happens and some pulling-apart force is added to the setting metallic parts, the prong portion is easily opened and the facetted precious stone may fall off.
Also, since the cutting of the facet cut precious stone is usually done by a crraftsman's hands, the proportions of each facet cut of the precious stones are not exactly the same proportion even in the same cutting style of the facet cut precious stone. On the other hand, jewelry parts are mainly manufactured by the casting method or the press cutting method in a factory. Therefore, the setting of metallic parts usually has a uniform proportion in the same style of the setting of metallic parts. Thus, a gap may be formed between the facets of the facet cut precious stone and the pressure contact-surface of the setting metallic parts. Consequently, correction work is needed to eliminate the gap and to contact the pressure contact-surface of the setting metallic parts and the facets of the facet cut precious stone closely, which has been done by cutting or polishing of each setting metallic parts by craftsman's hands.